Abstract

In a recent, population-based survey of 3,996 persons
in Indonesia, fluoroquinolone (FQ)-resistant Escherichia coli
was prevalent in the fecal flora of 6% of patients at hospital
admission and 23% of patients at discharge, but not among
healthy relatives or patients visiting primary healthcare centers
(2%). Molecular typing showed extensive genetic diversity
with only limited clonality among isolates. This finding
suggests that independent selection of resistant mutants
occurs frequently. FQ-resistant isolates exhibited a higher
rate of spontaneous mutation, but sparser virulence profiles,
than FQ-susceptible isolates from the same population. The
resistant isolates belonged predominantly to phylogenetic
groups A (57%) and B1 (22%) but also to the moderately virulent
group D (20%). Hypervirulent strains from the B2 cluster
were underrepresented (1%). Because FQ-resistant E.
coli can cause disease, especially nosocomial infections in
immunocompromised patients, spread of such strains must
be stopped.